Effect of chronic ethanol feeding on the hepatic secretion of very-low-density lipoproteins

Using Triton WR-1339 to inhibit plasma metabolism of VLDL, hepatic secretion of VLDL was measured in vivo in control and alcohol-fed rats. The composition of VLDL secreted from livers of chronically alcohol-fed rats was compared with pair-fed controls. The results show that the cholesterol, esterified and nonesterified, as well as the triacylglycerol content of VLDL secreted by the alcohol-fed rats was significantly reduced; protein and phospholipid constituents of the VLDL were unaltered. The apoprotein components of the VLDL showed no apparent difference between the two groups. However, fatty-acid composition of VLDL triacylglycerol and phospholipids show a significant reduction in 20:4 and an increase in 18:2 fatty acids in the alcohol-fed rats. VLDL secretion rates by chronic alcohol-fed rats was reduced significantly compared to the control animals, and this observation has been implicated in the pathogenesis of alcoholic fatty liver.